How efficient does a team have to be to cut down the nets? We have a clue. (Bob Donnan/USA TODAY Sports)

With all the Cinderellas and the buzzer-beaters and the late-night servings of “Onions!” in Bracketville, coupled with the simple reality that the season starts with 351 teams, it’s pretty much impossible in November to identify which teams have the chops of a champion, right? Well, yes and no.

Yes, tabbing the eventual title winner right now is guesswork at best. But thanks to a few numbers, we have a pretty good way to make sure that guess is educated, narrowing the field to a handful of legitimate contenders.

Thanks to the work of Ken Pomeroy (and Dean Oliver before him), we can quantify what a championship-caliber team looks like based on their adjusted offensive and defensive efficiency (defined here for the uninitiated).

Turning back the clock to 2002, the first season for which there’s efficiency data on KenPom.com, this is what we see when we look at the performance of national champions:

This info gives us a quick-and-dirty way to evaluate whether teams measure up to the standard of recent champs.

On average, teams that have sported nylon necklaces in April have produced an adjusted offensive efficiency rating (AdjO) of 111.8 – meaning they would be expected to score 1.118 points each trip down the court against an average Division I team. They also checked in with an average annual ranking of 7.5 in that category. That ranking is a little misleading, as it’s heavily influenced by Syracuse (No. 14 in 2003) and two Connecticut teams (No. 18 in 2011 and No. 39 in 2014) that drastically bucked the trend of the champ possessing a top-five offense. Defensively the champs check in with a mark of 90.3 (and a ranking of 9.6 on average).

What we’re most interested in though is their overall efficiency – namely the difference between their adjusted offensive efficiency and their adjusted defensive efficiency. The wider the gap, the stronger the team. Since this number provides the measuring stick for title winners’ overall efficiency, and for purposes of snappy marketing in the 18-35 demographic, let’s call it Winners’ Total Efficiency … or WTEff.

On average, title winners have posted a WTEff of 27.8 on average. That is pretty darn dominant. In fact, that’s superior to every team from the 2013-14 season.

What’s more informative than the average, though, is Connecticut’s mark of 20.4 posted last season. That’s the lowest total efficiency of any champion since 2002. Quite literally, last season’s Huskies lowered the bar for national champions.

This isn’t to disparage the glory brought to the Nutmeg State last spring. I would never disparage a team that could do what the mighty Whale could not by raising a championship banner at the Civvy, nor besmirch any state that produces the best pizza in the country. Particularly when it’s my home state.

Rather, I point this out to show how good a team has to be just to be considered in the championship conversation. It’s also a testament to how spectacular Shabazz Napier was in the NCAA tournament. Quick aside: Over the last five games of the season, Napier posted offensive ratings of 128, 114, 142, 139 and 111, an average of 124.8 over the final five games. For context, national player of the year Doug McDermott checked in at 124.4 for the season, so all Napier did was play better than the national player of the year for five straight games against some of the best teams in the country. No big deal. And just imagine how good he’d have been if he could have gotten a late-night sandwich or two.

But let’s get back to the teams and focus on the future: Who’s in the championship conversation to start the season? Based on the preseason projections from KenPom.com, we come away with seven teams who surpass the 20.4 WTEff threshold. The top seven as ranked by KenPom prior to the start of the season: Duke (26.2), Kentucky (25.7), Louisville (25.2), Kansas (22.5), Arizona (22.0), Wisconsin (21.4) and Florida (21.0).

Considering college schedules often open with such fearsome foes as Newman — an actual opponent of Wichita State — it could be a little while before teams’ true mettle is forged in the fires of conference play. To that end, we’ll check back to see which teams have the look of the champion throughout the year.